Method and device for controlling a gas flow over a throttle valve in an internal combustion engine

ABSTRACT

A method and a device for controlling a gas flow over a throttle valve in an internal combustion engine. The method and device can be used in particular in internal combustion engines in motor vehicles and allow for fast and accurate control of a gas flow while minimizing apparatus and control costs. A method is provided for controlling a gas flow over a throttle valve in a combustion over the throttle valve and the actual gas flow; and taking into account the determined difference when calculating the throttle setting.

FIELD OF THE INVENTION

The present invention relates to a method and a device for controlling agas flow over a throttle valve in an internal combustion engine. Thepresent invention concerns, in particular, a method and a device for usein automotive engineering.

BACKGROUND INFORMATION

An air/fuel mixture is ignited in the combustion chamber of an internalcombustion engine to generate an engine torque. The gas mass filling thecombustion chamber must be controlled and detected as accurately aspossible because it determines, among other things, the engine torque,the fuel volume to be injected, and the ignition point.

Using an “electronic gas pedal” in modern engine control systems, thepedal position is interpreted as a torque request. This torque requestis converted to a setpoint for the air mass flow. A “charge control”function calculates a setpoint air mass flow from the torque request andgenerates from this value a setpoint for controlling the throttle plate.A control element adjusts the throttle plate to the setpoint. Adownstream hot-film air mass sensor measures the actual air mass flow.Based on tolerances in the hot-film air mass sensor and in thecalculation path of the calculation of air mass flow over the throttlevalve, a difference is produced between the actual value and thesetpoint of the air mass flow and between the actual torque and thetorque request.

To correct these inaccuracies, an adjustment system that has not onlyone adjustment unit, but two adjustment units, is described in EuropeanPatent No. 575710. In a convention device, the first adjustment unitsends the actuating signal to the adjustment path, while the secondadjusting unit is used to calibrate the first adjusting unit. In theknown device, a throttle-plate-based charge signal is used to controlinjection, with this relatively fast adjusting signal being calibratedby an air mass meter in the stationary state.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a method and a devicefor controlling a gas flow over a throttle valve in an internalcombustion engine, thereby adjusting the gas flow quickly and precisely.In addition, it must be possible to carry out the method as well asproduce and operate the device economically.

The object is achieved, in particular, by providing a method forcontrolling a gas flow over a throttle valve in a combustion chamber ofan internal combustion engine having the following steps: calculation ofa throttle setpoint setting from the setpoint gas flow, activation ofthe throttle valve using the throttle setpoint setting, anddetermination of an actual gas flow, characterized by the followingsteps: calculation of a gas flow over the throttle valve on the basis ofan actual throttle setting, determination of a difference between thecalculated gas flow over the throttle valve and the actual gas flow, andtaking into account the determined difference when calculating thethrottle setpoint setting, in particular by adjusting the setpoint gasflow. In doing this, the setpoint air mass in the combustion chamber isadvantageously converted in one step to a throttle valve setpoint atwhich an actual air mass begins to form with the accuracy of the sensorused to determine the actual gas flow. A hot-film air mass sensor can beused, in particular, as the sensor for determining the actual gas flow.A further advantage lies in the fact that, unlike the related art, anadditional charge controller, which subsequently adjusts the setpointand actual mass, is not used. This reduces the production, maintenance,and operating costs. A further advantage lies in the fact that thesingle-step control stabilizes the throttle plate characteristic,thereby improving the operation of the entire internal combustion engineunit. A further advantage lies in the fact that the method makes itpossible to adjust the desired air mass flow very quickly and precisely.In the steady state, in particular, there is no difference between thesetpoint charge and the actual charge measured by the hot-film air masssensor.

In one particular embodiment of the present invention, the method ischaracterized by a determination of at least two correction quantitieswhen taking into account the difference between the gas flow over thethrottle plate of the throttle valve and the actual gas flow. This hasthe advantage that the determination of at least two correctionquantities makes it possible to achieve faster and more precise control.An additional advantage lies in the fact that the determination of atleast two correction quantities provides for the separate treatment ofand compensation for different error quantities and disturbances, thusfurther improving control accuracy and speed.

In a further embodiment of the present invention, the method ischaracterized by additively taking into account at least one firstcorrection quantity and multiplicatively taking into account at leastone second correction quantity, with the first and second correctionquantities being taken into account simultaneously or alternately, inparticular the first correction quantity being taken into account, i.e.,being relevant, primarily in the case of small gas flows and the secondcorrection quantity being taken into account, i.e., being relevant,primarily in the case of large gas flows over the throttle valve. In afurther embodiment of this design, the first correction quantitycorrects an error caused by leakage air over the throttle valve, and thesecond correction quantity corrects an error caused by an incorrectdetection of a pressure upstream from the throttle valve. This isadvantageous because it allows the two errors to be handled according totheir specific error characteristics, thus increasing control accuracy.One advantage lies in the fact that an error caused by leakage air,which is made noticeable by an additive error in any operating state,but is not relevant especially with small gas flows, can be treatedaccordingly. Likewise, an error caused by erroneous pressure detection,which is noticeable in any operating state and is relevant, inparticular, with large gas flows, can also be treated accordingly. Thetwo correction quantities can be preferably taken into accountsimultaneously, thus achieving a high control accuracy. Overall, anembodiment of this type provides very fast and yet highly accurate andreliable control, at the same time lowering costs of both equipment andcomputer-supported control.

In a further embodiment of the present invention, at least one of thecorrection quantities is stored at the end of operation of the internalcombustion engine. This advantageously provides full control accuracy assoon as the internal combustion engine resumes operation. The correctionquantities can be advantageously stored by appropriate electroniccomponents, for example by an SRAM component or a magnetic storagedevice.

In a further embodiment of the present invention, a predetermined valueis used as a starting value for at least one of the correction valueswhen operation of the internal combustion engine resumes. This isadvantageous because it allows a selected cold-start value to be easilydetermined for specific correction quantities. The provision ofpredetermined values is also advantageous because it maintains securecontrol even if the internal combustion engine is idle for an extendedperiod of time or if data or information relating to the predeterminedcorrection quantities is lost.

In a further embodiment of the present invention, the setpoint gas flowis determined on the basis of at least one request for the torque of theinternal combustion engine. This is advantageous because, in a motorvehicle with an internal combustion engine, not only can the torquerequest via the gas pedal be taken into account, but also torquerequests that are produced by an automatic transmission of the motorvehicle or by an anti-spin control system of the motor vehicle.

The object of the present invention is also achieved by providing adevice for controlling a gas flow over a throttle valve in a combustionchamber of an internal combustion engine including a throttle valvecontroller having an input signal for a setpoint gas flow and an outputsignal for a valve position, and a measuring sensor for determining anactual gas flow, characterized in that the throttle valve controller hasa computing device which calculate a gas flow over the throttle valve onthe basis of the throttle setting, and which further determines adifference between the calculated gas flow over the throttle valve andthe actual gas flow, with this difference being taken into account whencalculating the output signal, in particular by adjusting the setpointgas flow. A device of this type according to the present invention hasthe same advantages mentioned above in connection with the methodaccording to the present invention. In particular, a device of this typeis advantageous because it ensures fast and precise control, at the sametime reducing the apparatus and computing requirements so that a deviceof this type can be produced, maintained, and operated economically.

In one embodiment of the present invention, at least two correctionquantities are determined when determining the difference. This has theadvantage that even complex error quantities and disturbances can bedetected quickly and with relatively little effort, achieving stable andprecise control. This is particularly true when the at least twocorrection quantities separately detect error sources with additive andmultiplicative error characteristics and preferably take them intoaccount simultaneously.

The subject matter of the present invention also includes a device thatcarries out one of the above-mentioned control methods according to thepresent invention. This combines the advantages of fast and accuratecontrol with an economical implementation by a device according to thepresent invention.

The subject matter of the present invention also concerns a motorvehicle that has a device like the one described above.

The present invention also relates to data media which contain a controlprogram for carrying out one of the above-mentioned control methodsaccording to the present invention, or which contain the parameters thatare necessary or advantageous for carrying out one of theabove-mentioned methods according to the present invention. The datamedia can store the information in any form, in particular inmechanical, magnetic, optical or electronic form. In particular,electronic data media are advantageous, for example a ROM, PROM, EPROMor EEPROM device that can be advantageously inserted into correspondingcontrol units. Data media of this type can be used to easily exchangecontrol parameters and control programs, thus making it possible, forexample, to configure a standard control unit for different vehicletypes simply by inserting the corresponding data medium.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a block diagram for detecting a charge using a hot-film airmass sensor, and for determining two correction quantities.

FIG. 2 shows a block diagram for determining a gas flow over a throttlevalve.

FIG. 3 shows a block diagram for controlling the charge according to thepresent invention as well as for calculating the throttle valve angle.

FIG. 4 shows a device according to the present invention for controllinga gas flow over a throttle valve.

DETAILED DESCRIPTION

FIG. 1 shows a block diagram for the charge detection system, includinga hot-film air mass sensor, and for determining two correctionquantities msndko and fkmsdk. In the upper signal path of FIG. 1, an airmass flow mshfm measured by the hot-film air mass sensor is converted toa corrected relative charge r1 of a cylinder. To do this, air mass flowmshfm measured by the hot-film air mass sensor is first converted to anuncorrected relative charge rlroh of a cylinder. This is done throughdivision 111 of air mass flow mshfm measured by the hot-film air masssensor by a value that is derived from multiplication 112 of anengine-specific constant KUMSRL by engine speed nmot. Intake manifoldpressure ps is derived from uncorrected relative charge rlroh byapplying the gas equation and a corresponding integration 113. Correctedrelative charge r1 of the cylinder is calculated from intake manifoldpressure ps by the taking into account 114 of additional influencingquantities in relation to the flow rate ratios in the intake manifold.To convert the standard air mass flow to a mass flow at an instantaneoustemperature, the air mass flowing over the throttle valve is calculated115 from intake manifold pressure ps together with throttle plate anglewdkba of the throttle valve in relation to a stop and an intake-airtemperature-compensation factor ftvdk. FIG. 2 shows a detailedillustration of the calculation of the air mass flowing over throttlevalve msdk. Difference msdif is formed by a subtraction 116 frommeasured air mass flow mshfm and calculated air mass flow msdk. A firstadditive correction quantity msndko is derived by an integration 117 ofdifference value msdif. A second multiplicative correction quantityfkmsdk is calculated in the same manner by an integration 118 ofdifference value msdif. Integration operations 117, 118 also differ fromeach other, in particular, in terms of the integration constants, i.e.,the resulting physical unit. Additive correction quantity msndko isreturned directly to the calculation of throttle-valve gas flow 115.Multiplicative correction quantity fkmsdk is also returned to thecalculation of the throttle-valve gas flow by a multiplication 120 by anambient pressure pvdkds measured by a pressure sensor, determining aneffective pressure upstream from throttle valve pvdk. By taking intoaccount correction factors msndko and fkmsdk when calculating the gasflow over the throttle valve, the calculated value for the gas flow overthrottle valve msdk is brought into alignment with measured value mshfm.This improves the accuracy of this system in such a way that thecalculation of relative charge r1 can be based exclusively on calculatedgas mass flow msdk if necessary, for example if the hot-film air masssensor fails. This is done by flipping switch 119 according to acorresponding changeover signal B_ehfm.

In carrying out the multiplicative correction, for example, it isassumed that pressure value pvdk coming from the ambient pressure sensorlies within certain tolerances, producing a difference betweencalculated gas mass flow msdk and measured gas flow mshfm. Thecorrection responds to this difference by adjusting multiplicativecorrection quantity fkmsdk until msdk is equal to mshfm. Following asteady-state adjustment, quantity pvdk is identical to the actualpressure upstream from the throttle plate, if the other influencingquantities do not lie within the tolerances. Normally, the adaptationquantities cover all tolerances that occur in the hot-film air masssensor path and the throttle valve path, causing quantity pvdk to differfrom the actual pressure upstream from the throttle valve. Nevertheless,the adjustment serves its purpose, which is to adjust thethrottle-valve-based air mass flow calculation to the air mass flowcalculation based on the hot-film air mass sensor.

In an induction engine, quantity pvdkds can be derived from an ambientpressure sensor and, in a pressure-charged engine, it can be derivedfrom a charge-air pressure sensor upstream from the throttle valve. Inan induction engine with a hot-film air mass sensor and a pressuresensor in the intake manifold, pressure pvdkds can be derived from theintake manifold pressure via a level adaptation. If a pressure sensor isnot provided, value pvdkds is set to 1 and fkmsdk is set to the samevalue as pvdk, while in an induction engine, fkmsdk includes the ambientpressure information along with tolerance inaccuracies in the throttlevalve and the hot-film air mass sensor system.

FIG. 2 shows a block diagram for determining gas mass flow msdk over thethrottle valve according to calculation unit 115 in FIG. 1. Setpointangle wdkba of a throttle plate of the throttle valve is first availableas the input signal. Setpoint angle wdkba is preferably related to thethrottle plate stop. Using a transfer function MSNWDK 201 established inan air test bay, mass flow msndk is calculated downstream from thethrottle valve. Additive correction quantity msndko, which preferablydetects the leakage air over the throttle valve under normal conditions,is added 202 to mass flow msndk. The value resulting from this addition202 is multiplied 203 by an intake-air temperature-compensation factorftvdk for converting the standard air mass flow to an air mass flow atan instantaneous temperature. At the same time, a correction factorfpvdk is derived from a pressure value pvdk upstream from the throttleplate of the throttle valve by division 204 by nominal pressure value1013 hPa to adjust the air mass flow at normal pressure upstream fromthe throttle valve to instantaneous conditions. Value pvdk ismultiplicatively composed of an ambient pressure pvdkds measured by apressure sensor and multiplicative correction factor fkmsdk, as shown inFIG. 1. At the same time, a correction factor KLAF (ps/pvdk) is alsoderived, by quotient formation 205, from intake manifold pressure ps andthe pressure upstream from the throttle plate of throttle valve pvdk anda subsequent transfer function 206, which is also known as the outflowcharacteristic and which adjusts the standard flow through the throttlevalve measured at an above-critical flow rate to below-critical flowrates. The two derived correction factors fpvdk and KLAF (ps/pvdk) areeach taken into account along with the mass flow by a multiplication207, 208. To summarize, air mass flow msdk is calculated as follows:

msdk=msndk×ftvdk×fpvdk×KLAF (ps/pvdk).

FIG. 3 shows the charge control system according to the presentinvention by calculating the setpoint angle of the throttle plate ofthrottle valve wdks from the setpoint for air mass flow mssol. In thiscase, the setpoint for air mass flow mssol is first altered according todifferent correction quantities. Many of the components of the chargecontrol system according to the present invention are constructed in aninverse relationship to the charge detection system illustrated in FIG.1. In particular, correction quantities msndko and fkmsdk determinedduring the course of charge detection are used in the charge controlsystem according to the present invention. As shown in FIG. 1, theparameters of engine speed nmot and KUMSRL are first multiplied 112.Setpoint mssol is divided by the resulting product, yielding a setpointcharge rlsol in the combustion chamber. Further division 302 of thisvalue by a conversion factor fupsrl, “intake manifold pressure inrelative charge” and a subsequent addition 303 to a correction factorpirg, which takes into account the partial pressure of the internalexhaust gas recirculation, yields setpoint pressure pssol in the intakemanifold. This value pssol is altered by a division 304 by a pressurepvdk upstream from the throttle plate of the throttle valve andtransferred to a transfer function 305, which is also known as the“outflow characteristic” and adjusts the standard flow through thethrottle valve measured at an above-critical flow rate to below-criticalflow rates. Value pvdk is calculated by multiplication 306 from ambientpressure pvdkds measured by a pressure sensor and multiplicativecorrection factor fkmsdk, just like the calculation shown in FIG. 1. Thevalue derived from outflow characteristic 305 is subsequently adjustedby a multiplication 307 by an intake-air temperature-compensation factorftvdk to convert the standard air mass flow to an air mass flow at aninstantaneous temperature, and subsequently by a multiplication 308 by acorrection factor fpvdk to adjust the air mass flow at normal pressureupstream from the throttle valve to instantaneous conditions for theinstantaneous temperature and pressure ratios. Correction factor fpvdkis derived from pressure pvdk upstream from the throttle plate of thethrottle valve by division 309 by a nominal pressure of 1013 hPa. Thevalue resulting from the calculations described above is subjected to adivision 310 together with setpoint mssol for the air mass flow.Additive correction value msndko, which takes into account the leakageair over the throttle valve under normal conditions, is subsequentlysubtracted from the value reached by division 310. Resulting valuemsnwdks is transferred to a transfer function WDKMSN 311, which yieldsthe inverted characteristic of transfer function MSNWDK shown in FIG. 2and thus a setpoint angle wdks for the throttle plate of the throttlevalve derived from the corrected and adjusted setpoint for air mass flowmsnwdks. FIG. 4 shows the device according to the present invention forcontrolling a gas flow over a throttle valve. Setpoint mssol for the airmass flow is determined from the position of a gas pedal 401. As shownin FIG. 3, charge control system 402 derives a setpoint angle wdks of athrottle plate 403 from this value. Actual angle wdkba of the throttleplate is detected and serves as an input quantity for charge detectionsystem 404. As shown in FIG. 1, charge detection system 404 derives massflow msdk over the throttle valve from value wdkba. A hot-film air masssensor 405 connected downstream in intake manifold 400 determines airmass flow mshfm. As shown in FIG. 1, an additive correction value msndkoand a multiplicative correction value fkmsdk are derived from valuesmsdk and mshfm in a comparator and integrator module 405. The twocorrection values are output to both charge control system 402 andcharge detection system 404, where they serve as input quantities. Theadvantage of this device according to the present invention is not onlythat charge control system 402 can set a throttle plate angle at whichthe setpoint matches the value measured by the hot-film air mass sensorwithout any subsequent correction by a relatively slow controller, butalso that, in an injection system located upstream from the intake valvein which the air mass flow at the time the intake valve closes should beknown, the throttle plate angle achieved at this later point in time iseasier to estimate than a future air mass flow based on the hot-film airmass sensor signal. The future air mass flow can be calculated on thebasis of this future throttle plate angle, and thus the instantaneousinjection time advantageously corrected, with the correction factorsmaking this prediction just as accurate as the hot-film air mass sensor.

Abbreviations

B_ehfm Error signal, changeover signal. fkmsdk Multiplicative correctionquantity. fpvdk Correction factor for adjusting the air mass flow atnormal pressure upstream from the throttle valve to instantaneousconditions = pvdk/1013 hPa. ftvdk Intake-air temperature-compensationfactor for converting the standard air mass flow to an air mass flow atan instant- aneous temperature. fupsrl Conversion factor for the intakemanifold pressure in a re- lative charge. KLAF Outflow characteristicfor adjusting the standard flow mea- sured at an above-critical rate offlow to below-critical rates of flow. KUMSRL Parameter for determiningthe relative cylinder charge from the air mass flow and the enginespeed, piston-swept volume. msdif Difference between the calculated andmeasured gas mass flow = mshfm - msdk. msdk Calculated air mass flowover the throttle valve. mshfm Air mass flow measured by the hot-filmair mass sensor. msndk Mass flow downstream from the throttle valve.msndko Additive correction quantity, leakage air over the throttle valveunder normal conditions. msndks Setpoint for air mass flow under normalconditions. MSNWDK Standardized air mass flow over the throttle valve,measured in an air (wdkba) test bay. msnwdks Adjusted setpoint gas flowover the throttle valve. mssol Setpoint for the air mass flow underinstantaneous conditions. nmot Engine speed. pirg Correction of theintake manifold pressure by exhaust gas recirculation, partial pressureof internal exhaust gas recirculation. ps Pressure in the intakemanifold. pssol Setpoint pressure in the intake manifold. pvdk Pressureupstream from a throttle plate of the throttle valve = pvdkds × fkmsdk.pvdkds Ambient pressure measured by a pressure sensor. rlroh Air massflowing into the intake manifold, uncorrected relative charge of acylinder. rl Air mass flowing out of the intake manifold, correctedrelative charge of a cylinder. wdkba Actual angle of a throttle plate ofthe throttle valve in relation to a stop. wdks Setpoint angle of athrottle plate of the throttle valve in relation to a stop = WDKMSN(msnwdk). WDKMSN Inverted characteristic of MSNWDK.

What is claimed is:
 1. A method for controlling a gas flow over athrottle valve into a combustion chamber of an internal combustionengine, comprising the steps of: determining of an actual gas flow;calculating the gas flow value over the throttle valve as a function ofan actual throttle setting; determining a difference between thecalculated gas flow over the throttle valve and the actual gas flow;calculating a throttle setpoint setting as a function of a setpoint gasflow and the determined difference; activating the throttle valve usingthe throttle setpoint setting value; determining at least two correctionquantities; determining the difference as a function of the at least twocorrection quantities; and storing at least one of the at least twocorrection quantities at an end of an internal combustion engineoperation.
 2. A method for controlling a gas flow over a throttle valveinto a combustion chamber of an internal combustion engine, comprisingthe steps of: determining of an actual gas flow; calculating the gasflow value over the throttle valve as a function of an actual throttlesetting; determining a difference between the calculated gas flow overthe throttle valve and the actual gas flow; calculating a throttlesetpoint setting as a function of a setpoint gas flow and the determineddifference; activating the throttle valve using the throttle setpointsetting value; determining at least two correction quantities;determining the difference as a function of the at least two correctionquantities; and when an operation of the internal combustion engineresumes, utilizing a predetermined value as a starting value for atleast one of the at least two correction quantities.
 3. A motor vehicle,comprising: an internal combustion engine including a combustion chamberand a throttle valve; and a device controlling a gas flow over thethrottle valve in the combustion chamber, the device including ameasuring sensor and a throttle valve controller, the measuring sensordetermining an actual gas flow, the throttle valve controller includinga computing arrangement, the computing arrangement calculating a gasflow over the throttle valve as a function of at least one throttlesetting, the computing arrangement determining a difference between thecalculated gas flow over the throttle valve and the actual gas flow, thethrottle valve controller having an input signal for a setpoint gas flowand an output signal for a valve position of the at least one throttlesetting, the computing arrangement calculating the output signal as afunction of the determined difference.
 4. A computer-readable datastorage medium storing a set of instructions, the set of instructionscapable of being executed by a processor to control a gas flow over athrottle valve into a combustion chamber of an internal combustionengine, the set of instructions performing the steps of: determining ofan actual gas flow; calculating the gas flow over the throttle valve asa function of an actual throttle setting; determining a differencebetween the calculated gas flow over the throttle valve and the actualgas flow; calculating a throttle setpoint setting as a function of asetpoint gas flow and the determined difference; and activating thethrottle valve using the throttle setpoint setting.
 5. Acomputer-readable data storage medium storing parameters, the parametersfor controlling a gas flow over a throttle valve into a combustionchamber of an internal combustion engine by performing the steps of:determining an actual gas flow; calculating the gas flow over thethrottle valve as a function of an actual throttle setting; determininga difference between the calculated gas flow over the throttle valve andthe actual gas flow; calculating a throttle setpoint setting as afunction of a setpoint gas flow and the determined difference; andactivating the throttle valve using the throttle setpoint setting.
 6. Amethod for controlling a gas flow over a throttle valve into acombustion chamber of an internal combustion engine, comprising thesteps of: determining of an actual gas flow; calculating the gas flowvalue over the throttle valve as a function of an actual throttlesetting; determining a difference between the calculated gas flow overthe throttle valve and the actual gas flow; calculating a throttlesetpoint setting as a function of a setpoint gas flow and the determineddifference; activating the throttle valve using the throttle setpointsetting value; determining at least two correction quantities;determining the difference as a function of the at least two correctionquantities; and determining the difference by adding at least one firstcorrection quantity of the at least two correction quantities andmultiplying at least one second correction quantity of the at least twocorrection quantities.
 7. The method according to claim 6, wherein theat least one first correction quantity corrects a first error caused byleakage air over the throttle valve, and wherein the at least one secondcorrection quantity corrects a second error which is caused by anincorrect detection of a pressure upstream from the throttle valve.
 8. Adevice for controlling a gas flow over a throttle valve in a combustionchamber of an internal combustion engine, comprising: a measuring sensordetermining an actual gas flow; and a throttle valve controllerincluding a computing device, the computing device calculating the gasflow over the throttle valve as a function of at least one throttlesetting value, the computing arrangement determining a differencebetween the calculated gas flow over the throttle valve and the actualgas flow, the throttle valve controller having an input signal for asetpoint gas flow value and an output signal for a valve position valuethe computing arrangement calculating the output signal as a function ofthe determined difference.
 9. The device according to claim 8, wherein,when the computing arrangement determines the difference, the computingarrangement also determines at least two correction quantities.
 10. Thedevice according to claim 8, wherein the computing arrangementcalculates a throttle setpoint setting as a function of a setpoint gasflow and the difference, throttle valve being activated using thethrottle setpoint setting.
 11. A method for controlling a gas flow overa throttle valve into a combustion chamber of an internal combustionengine, comprising the steps of: determining of an actual gas flow;calculating the gas flow value over the throttle valve as a function ofan actual throttle setting; determining a difference between thecalculated gas flow over the throttle valve and the actual gas flow;calculating a throttle setpoint setting as a function of a setpoint gasflow and the determined difference; and activating the throttle valveusing the throttle setpoint setting value.
 12. The method according toclaim 11, further comprising the step of: determining at least twocorrection quantities; and determining the difference as a function ofthe at least two correction quantities.
 13. The method according toclaim 11, further comprising step of: determining the setpoint gas flowas a function of at least one request for torque of the internalcombustion engine.